The present invention relates to a photosensitive material for use in electronic photography having a photosensitive layer comprising a selenium arsenic alloy. A photosensitive material of this type is used in electronic photography equipment such as plain paper copying machines and the like, and is generally characterized by a photosensitive layer deposited on a conductive substrate, such as an aluminum alloy.
During operation of the above described electronic photography equipment, the surface of the photosensitive layer is uniformly charged by corona discharge in a darkened environment. The surface of the layer is then exposed to a picture image, and the electric potential present acts to create an electrostatic latent image on the surface. Toner then adheres to the electrostatic latent image, and the image is thereafter transferred to a paper sheet and fixed thereto by heat or pressure to become a permanent copied image. The toner remaining on the surface of the photosensitive layer is removed in a cleaning process utilizing a fur brush and blade. The remaining charge (potential) is removed by AC discharge and/or optical discharge to prepare for the beginning of the next cycle.
There is, however, a problem that exists. The photosensitive layers tend to have varying charge potentials due to the varying corona discharge of the photosensitive materials used. This is the case even where the photosensitive layers have the same composition and same film thickness. The result is that the charging ability per unit film thickness varies for different layers produced. This causes a great problem with respect to quality control, for if the charging ability is too low, the contrast of the picture image will deteriorate. The charging ability per unit film thickness is represented by the formula EQU V.sub.o /I.sub.pc.L
where the charge potential is represented by V.sub.o, the current flowing into the substrate is I.sub.pc, and the film thickness is L.
It is thus an object of the present invention to provide a photosensitive material which avoids the variation in charging ability per unit film thickness by controlling the photosensitive layer through conditions other than the composition or the film thickness.